How to Lie
by kedgeree
Summary: When John needs to return to Mary and pretend to feel love when he does not, he turns to his best friend for a lesson in lying. **SPOILERS FOR S3: missing/alternate scene from His Last Vow


**How To Lie**

* * *

"You don't have to do this, John."

"I do, though, don't I?" John said grimly.

Sherlock turned Mary's flash drive over and over between his thumb and forefinger, feeling the cool metal against his skin and watching the initials A.G.R.A. change into blank silver over and over. Reality and fantasy, spinning in a never ending cycle, chasing each other's tails. "There are other options," he said.

John's hands were steady on the arms of his chair—_John, back in his place, but not home again_—but it was the only façade of calm his body could convincingly achieve. John was trying so hard to prove to himself he was calm that his mouth was pressed into a white-cornered line of pain. K_iss softness into it_. Veins stood out on his temples beside the deep grooves in his brow—_touch, smooth it all away_—and his body looked like it might fold in on itself with tension at any moment—_detonate him, let him rage_. His face seemed set in cold, craggy stone, resistant to being warmed by the tentative flickers of red-gold light from their fireplace.

"What options?" The corner of John's mouth curled up in wry challenge. "You saw what was on there, the same as I did. And you're the one who saw what _wasn't_ on there. She's not exactly _retired_ from that work, hm? You know I'm the only one who can get close enough to her to find out the rest, what she's really up to. And then there's the ba—" John's voice caught, his throat constricted. He swallowed down the unfinished word. "I have to go back to her."

Sherlock stopped turning the drive in his hand and frowned down at it. There was no response he could offer his John but a small shake of his head. He covered Mary's initials with his thumb. _Hold him down. Don't let him go back to war._

"John, she reads people. She'll see through you."

"Maybe." John jerked his chin up in defiance.

"John," Sherlock said reproachfully, "you know it's true. You don't lie. You're not good at it."

"Then teach me."

Sherlock blinked. "What?"

"You're the bloody _expert_, aren't you?" John's eyes were cold. "Teach me how to lie."

"John, it's not…that simple."

"I didn't ask if it was _simple_."

"John, you're married."

"I'm well aware of that, Sherlock."

"You're…_intimate_."

John's bark of laughter was utterly humourless. "Yeah, I used to think you didn't really understand about that sort of thing. And then I saw you with Janine. That looked pretty _intimate_ to me, and you had to make _that_ convincing, didn't you?" John leaned forward in his chair, eyes locked on Sherlock's. His voice held a snarl even though his mouth was held in a small, tight smile. "So _teach me_. Because I have to make _this_ convincing, too."

He did not want to think about John with Mary. _John in Mary._ Not like _that. Sweat and rushing blood. _He might not have experienced the sensations himself—not with Janine, not with anyone—but Sherlock had never lacked for imagination._ Hot, sticky, slippery._

"John, I don't understand what you're asking me to do."

John leaned even closer, his thighs parting wider. "Yes. You do."

"You don't want this," Sherlock whispered. His heart was pounding. He set the flash drive carefully on the arm of his leather chair and rubbed his thumb and forefinger together. Fantasy and reality, turning, turning.

"We're willing to do _anything_, aren't we, you and I?"

Sherlock's veins felt washed with cold water, freezing his body in place while his mind roared in protest inside its frigid cage. _No._ _You're not supposed to be like that. Not like me._

John stood slowly and stepped forward into the space between Sherlock's feet. "If I'm going to learn to lie, I might as well go big. And what could be a bigger lie," he gestured from his chest to Sherlock's, "than _this_?"

Sherlock's head jerked back, the sting of John's words was so palpable. His mouth opened and, as so often was the case when his brain seemed to short-circuit, words spewed out. "Eye contact. Not too much, not too little. Don't nod when you're trying to be convincing. Say less than you think you need to. Keep your hands still. Micro expressions are—"

"Sherlock," John cut sharply across his prattle, his voice low and dangerous. "Shut up. Stand up," he ordered.

Sherlock rose in a fluid movement. John did not step back. His generic, everyman's plaid shirt—_disguise_-was untucked and Sherlock was abruptly aware of the warmth he would feel against his palm if he slid his hand up and underneath those rumpled shirttails.

"You know what I need. _Teach me_." John looked up at him and smiled. It was the smile that said _heel, Sherlock,_ while John's eyes snapped the leash. His next words were almost a growl. "_Show_ me what you did withyour_ girlfriend_."

Sherlock raised his hand slowly, as though he were slipping into a trance, and brushed John's cheek with the edge of his thumb. Just a test, just a taste. John's jaw was rough with stubble and his forehead bore a faint sheen of oil and sweat, messy and human and _real_. He touched his fingertips to the soft, greying blond hair at John's temple. John didn't flinch away. John didn't look at him with disgust or horror. John sighed and closed his eyes and leaned his head into Sherlock's hand and—_oh, God_.

"You don't care…?" Sherlock summoned his faltering voice from where it had lost itself deep inside his chest. "You don't care that I'm…?"

"What? A man? My best friend? That it's not _your area_?" John laughed, sad and bitter. "You know, I always thought you were…well…"

_Wrong_.

"I know what you thought," Sherlock said. He slid his hand around to the back of John's head and pulled him into a kiss. John made a small, startled sound in the back of his throat.

Sherlock meant the kiss to be soft, gentle, but when John's lips parted against his, he groaned and broke open and _took._ John's mouth tasted of sorrow, and Sherlock would suck every drop from his tongue and breathe his name back into him, "_John_."

When Sherlock ended the kiss, John looked stunned.

"Telling a lie is one thing," Sherlock said, remembering his purpose. He let his mouth brush against John's as he spoke, unwilling to allow distance between them again. John's skin was so warm, warmer than he'd imagined. "Acting it out with your body is…something else. But there are ways."

"Go on," John said roughly.

"You know already. How do you sell a lie, John?"

John moved his hands to Sherlock's chest, neither holding nor pushing away. Steady hands. "You wrap it in the truth."

Sherlock slid his lips across John's cheek and spoke close to his ear. His voice dropped to its lowest register, scraping out his deepest truths. "I want you, John. I've always wanted you and I always will." He kissed the edge of John's jaw, nipped at the soft skin below his ear. He smelled of long nights chasing danger and of falling into safe, clean sheets. "Do you believe me?"

Dismayed laughter puffed against Sherlock's neck. "You know, I—almost—"

With a deep breath for courage, Sherlock reached for John's hand, pulled the palm down against his thigh, and then slid it between his legs and up.

John's eyes grew wide when he felt the swell and blood heat of Sherlock's erection through his trousers. "You're…"

"Hard. Yes."

"How? If you don't…really want me. How?"

Sherlock moved John's hand to his hip so he could press closer to his body. John's thigh fit between his perfectly. _Perfect._ He rubbed himself against John's hip and his mouth opened in a silent gasp of pleasure. "It _feels_..." Sherlock squeezed his eyes shut. "The…the anticipation of physical pleasure, touch, friction is a natural physiological response. And in this…lesson, your body is a tool. A weapon. Let it be primed. Don't try to talk it out of what it feels."_ So good._

"Okay." John's eyelids fluttered. "I…I'll try."

Summoning scattered pieces of what knowledge he possessed of giving pleasure, Sherlock slid his hands back around John's body, rubbing circles into the muscles of his lower back with a pressure designed both to soothe and to urge John's hips rhythmically closer to his own. With a low rumble of encouragement, he bent his head, kissing and nipping a trail across John's neck until, nosing into his shirt collar, he found a spot that made him gasp and shudder.

"Sherlock!"

Sherlock heard both the awareness and the confusion in John's exclamation. "Just _feel_ it, John. Close your eyes. Visualize whatever you need to see—no one will know."

John's breath was shaky now. His hands moved experimentally but not tentatively over Sherlock's body, sliding up his waist and over his shoulders, exploring new territory.

"Is that what you did with Janine?"

_Janine_ again. Sherlock frowned and nipped harder at the tender spot on John's neck. John responded with a raw, lustful sound that hissed down Sherlock's body and flared between his hips, hot and tight. "Does it help," he asked darkly, "imagining me touching _her_? Our bodies together? My fingers inside her? Her mouth on my prick? My tongue between her legs? Kissing her? Fucking her?" Some of those things had happened. Some had not.

John whimpered like he was in pain. "Is that what _you're_ thinking about now?"

"No."

"Tell me—"

"You. I'm thinking of you." _Your body. Your hands. Your mouth. No one but you._

"Liar," John huffed. His eyes were uncertain.

"You think so?" Sherlock murmured, guiding John's hands to his hips so he could feel their movement as he slowly and deliberately ground his erection against him again. "Words that aren't true don't have to be lies."

"What…what does that mean?"

"Redefine your words. Define them any way you need so that you can say them like truth. Make 'I want you' mean 'I hate you' if you must, as long as you can say it out loud _like the truth_. Rehearse them, if you have to. How can you know what I really mean when I tell you how much I _want_ you now?" _Want you. Need you. _"How could you ever _know_? Do you understand?"

"Yes," John said hazily, "I think so. I…it's hard to…think…like this."

Sherlock wrapped his shaking hands around John's upper arms, heady at the thought that John was affected. By _him_. God, he never wanted this to stop, this agony of possibility. "That's the point, John. You don't have to _think_. You don't have to remember tricks. It's not a _trick_," Sherlock said. "The key to lying is that it is _never_ a _lie_. It's a different truth. Believe it and act it out. That's the lesson. That's all there is." He bared his teeth in domination of his desire and pushed John away.

John took a step back and swayed, blinking out his confusion. His cheeks were flushed. Sherlock breathed hard into the long pause until John's eyes focussed on him again and his gaze sharpened with determination.

"Oh, no," John shook his head slowly, "Don't tell me that's _all_."

"John…are you sure?"

"See this through with me, Sherlock, this _lesson_ of yours," John growled, stepping back into Sherlock's space, drawing their bodies together again, "Because _I'm_ going to have to see it through."

Sherlock stared into John's fierce gaze and drew a long, shaky breath. "Go into the bedroom."

John nodded once, turned on his heel, and walked through the kitchen toward Sherlock's bedroom. His military walk. Determined.

Sherlock swallowed hard several times. This was not what he'd dreamed of, but then again a dream was all it had ever been before tonight. A desperate dream that saw him through so many nights alone, a fantasy no one would ever know, where he could love John Watson without reservation, like a whole man. Just the two of them, and no world beyond their bed.

But this was real, and Sherlock could only be the man he was. If this was going to be the first time-the only time-Sherlock would accept and embrace the razor wire-wrapped gift of this night. He would not waste it.

He went to the bedroom.

The lamp on the bedside table cast a gentle glow over the room, bringing out the gold in John's greying blond hair, softening the lines of his face. He had shed his button-up and was standing next to Sherlock's bed in his jeans and white vest, toeing off his brown brogue shoes.

Sherlock paused in the doorway, watching, and John's movements slowed. So many times John had been his bedroom, but this awareness that crackled between them had never been there before. "Go on." Sherlock dropped his chin and looked at John through the dark filter of his lashes. He touched the tip of his tongue to the backs of his upper teeth and inhaled. "All of it."

He saw John's Adam's apple bob before he reached for the bottom of his vest and then tugged it up and over his head. Sock feet and jeans and bared chest. Ruffled hair. An average man, a beautiful man, scarred and soft and perfect. His hands drifted past the line of hair that ran downward from his navel, hesitating at the buttons of his jeans. He looked at Sherlock, blinked his long, gold-tipped lashes.

"Do you feel vulnerable, John?" Sherlock whispered.

"Yes." John's voice was a whisper, too, but he did not flinch.

"Good." He took two long strides toward John and pulled him into a crushing, hungry kiss. "The sounds, the sensations of pain, distress, hurt—they can sound like passion. Let them out." He leaned in and kissed John's neck and put the flat of one hand against John's exposed belly. "Make noise," he growled. _Let me hear._

When he moved his mouth to the scar on John's shoulder, John whimpered. Sherlock bit down on the patch of ruined flesh, and John cried out.

"_Good_. Pain can sound like pleasure. Don't hide it. Don't hide any of it. This is how you lie, John." Sherlock unbuttoned his own shirt deftly and quickly. "You don't hide _anything_." He stripped the shirt off, then unfastened his trousers and pushed them down to the floor along with his pants.

Breathing hard and with a fumbling inelegance, John mirrored his actions, unbuttoning his jeans and stepping out of them. He sat down on the edge of the bed to pull his socks off, then rose again slowly to stand in front of Sherlock.

Sherlock's eyes slid down his body, drinking in the sight, memorizing every detail of the parts of John he had never been able to examine before. His heart gave one hard beat of shame, but _no_—tonight he was _allowed_ to look. Allowed to _touch_.

When he held his arms out, John stepped immediately into his embrace. Sherlock squeezed his eyes shut until he saw red, overwhelmed by the feeling of his skin touching John's. The boundary between their bodies blurred where the cells from their skin mingled. Hands, thighs, bellies, cocks, the anatomy was irrelevant, but Sherlock pressed into that connection, and felt it in every part of his irrelevant anatomy.

"Put it all together, John. Choose your words. Let your body respond. Show your pain as passion, your fear as reverence. Your test. Your game. Show me."

John nodded against his shoulder and his hands slid up Sherlock's back. He turned his head and kissed the side of Sherlock's neck, a brief, tender, almost tentative press of his lips. Sherlock's head arched back and fear trembled out of him in a shaky breath, waiting for John to find his way to the rest of his body, afraid of being overpowered by his own responses.

"Mary," John whispered against his ear.

Sherlock jolted. "No!" he choked out, clutching John to him desperately. "_My_ name. You're with _me_."

John stiffened in his arms. Sherlock felt his slow, controlled breaths against his skin. "Sh…Sherlock," John said quietly, and his hands on Sherlock's body steadied. "Sherlock," he repeated in a stronger, deeper voice.

Sherlock melted into him, "Touch me, John."

"_Sherlock_." John's hands started to move again, down his back, over the swell of his arse, to the backs of his thighs, where he squeezed Sherlock against him.

Sherlock groaned and grabbed the sides of John's head, tilting his face up, kissing his mouth hungrily. John kissed him back with equal fervour, angry, biting kisses that called his blood to his lips and his cock at the same time. This time when he hitched his hips against John's, with no barriers of clothing between them, the rough edge to the friction was a mirror to the rough edge of his emotion, an exquisite mix of pleasure and pain. He thrust into the sensation helplessly, and felt an answering swell of heat against his thigh.

"John," he breathed, reaching down for evidence of John's arousal. When he found it, he filled his palm, squeezing John's cock until he moaned out the sound of the pride Sherlock felt. "_Tell_ me how good I make you feel," he pleaded.

"I…you do." John's eyes were shut tight, and he pushed himself into Sherlock's hand. "I _feel_ it."

"Touch me back," Sherlock begged, and John's hand wrapped around his cock and started to move.

One kiss would have been enough for him to live on, more than he'd ever expected. One warm touch against his bare skin, that would have been enough. The breathless note of desire in John's voice, that might have been enough. But he had gone too far. He had been right to be afraid of taking this taste, because he would live hungry for the rest of his days. It would never be enough.

When Sherlock's knees folded, he made a grab for John's shoulders and disguised his fall as a twist that brought them down onto the bed together. Sherlock shifted himself up, trying to pull his legs up onto the bed, trying to pull John along with him. John would not be directed, though. Repositioning himself, he held Sherlock's hands against the bed and kissed his way from Sherlock's hip up his chest to his neck and finally to his mouth. Sherlock was painfully aware of every part of John's body that brushed against his eager erection as he moved. When John kissed him, letting his full weight rest atop Sherlock's body, Sherlock almost whined with need and wrapped his arms around John's shoulders and his legs around John's hips.

"How are we going to do this?" John asked around kisses, reaching up to push his fingers into Sherlock's hair.

"How?" Sherlock asked, dazed with lust, nudging his head toward John's hands for more petting, wriggling to rub his cock against John's for more friction.

"Do you have lube? Condoms?"

"No." A wave of alarm washed over Sherlock. Should he have those things? He mentally scrambled for acceptable alternatives, but his mind had gone blank. His eyes widened with panic. "I can…we could…"

"Sherlock. Shh. It's all right." John pushed himself up on one arm and licked his lips. His eyes were dark and so…honest. "Never mind. Here…" He kissed his way back down Sherlock's body, slowly, sometimes pausing to inhale the scent of the skin on different parts of his body, sometimes flicking his tongue out to taste. Sherlock held his hands around John's head, stroking his thumbs through his short, thick hair, as he squirmed with pleasure at each unexpected touch.

When John's mouth reached the bullet wound in Sherlock's chest, just barely healed, Sherlock heard his breath catch. He rested his head against Sherlock's chest for a moment, rubbing his cheek softly against Sherlock's skin. Sherlock shivered at the brush of stubble against his smooth flesh.

John held his fingertips over the fresh scar. He made an odd, choked noise, and plunged the rest of the way down Sherlock's body to his hips and took Sherlock's cock into his mouth.

Sherlock's body arched up and fell again like a string that had been plucked, vibrating with pleasure. John gripped his hips and sucked hard on the head of his cock, almost painfully hard, then stopped and licked him from balls to crown, almost painfully softly.

Sherlock realized his body had gone rigid when John stopped and laughed, and the glimpse of his old, playful humour almost broke Sherlock's heart. "You know I've never done this before, right?"

"John," Sherlock pulled himself up to reach for John's shoulders, but John pulled away.

"So I could use a little feedback," he said in the impatiently patient voice he used when Sherlock was being slow on social etiquette.

"Anything," Sherlock rasped out. "_Anything_ you do, John."

"So…this?" John wrapped his hand around Sherlock's cock again and started stroking him, watching his face. Sherlock had never felt so naked, so exposed. There was nowhere for him to hide. He gasped out John's name and then his mouth stayed open, making grunting, gulping, needy sounds as John worked his cock, their eyes locked together. "Yeah," John breathed. "It looks like _this_ works."

"Please." Sherlock pushed himself into John's hand. "John. Please."

"Please, what?" John growled, soldier and predator. "Am I going to make you come, Sherlock?"

"_Yes_," Sherlock gasped, grabbing for John's arms, trying to pull himself closer. _John_. His abdominal muscles squeezed while his thighs trembled uselessly, his whimper became a shout, and John's hand pulled his orgasm out of him. _John's hand_. He thought he might cry. He thought his fingers might tear through John's flesh. He thought he might melt into the sheets, through the floor, through the earth, he felt so saturated with ecstasy.

When he realized his eyes were closed, he opened them to see John moving to straddle his hips. He was panting hard, flushed, like he'd been running—_they used to run through London together_—and his eyes were locked, wide and amazed, on Sherlock's face. He swiped a hand through the ribbons of semen striping Sherlock's belly, wrapped his hand around his own erection, and began masturbating himself hard and fast.

"John." Sherlock reached for John's hips. He should be doing something. Something for John. _Hold him_. "John, tell me."

John leaned forward, bracing himself with one hand digging into Sherlock's bicep. He groaned when Sherlock's fingers tightened on his hips.

"Tell me you love me," Sherlock said urgently.

John collapsed onto his elbow, his left hand still stroking frantically. "Part of…the test?" he gasped.

Sherlock pulled him the rest of the way to his body, John's hand was caught between them, but he didn't slow or stop his movements. His knuckles slid against Sherlock's slicked skin, faster, faster. His face screwed up. Like pain.

"Tell me," Sherlock pleaded, raking his big hands down John's back, clumsy in his desperation. "Tell me. Make me believe it."

"I—"

"John, _make me believe it_."

"_I love you_," John gasped brokenly, then his hips hitched forward sharply and a new wet warmth pulsed into the space between their bodies. John fell forward and panted against Sherlock's neck. "God, I love you, Sherlock."

"_John_," Sherlock breathed reverently. _Only you. More than anything. More than anyone. _He nuzzled at the side of John's head, kissed the top of his ear, held him in his arms and with his blurred eyes until John's breathing slowed and his body relaxed.

Just the two of them, and no world beyond their bed. For one more breath. And another. And another. And—

"I have to go," John said. His voice was flat. "She'll be waiting."

When he rolled away, he didn't look at Sherlock. The air that hit the damp, sticky patch on Sherlock's belly felt cold. The empty space in between Sherlock's arms felt cold.

John stood, walked to the bathroom, and closed the door behind him. Sherlock listened to the sounds of running water and stared at the flat, white ceiling.

"I'll dress out there," John said when he re-emerged, his hips wrapped in one of Sherlock's blue and grey-striped towels. He nodded toward the sitting room and bent to gather his clothes from the floor.

Sherlock swallowed around the lump in his throat. There was nothing more to say.

"Just one last thing." John paused in the doorway without turning around. "How did I do? Did you believe me?"

Sherlock closed his eyes and said, "Yes."


End file.
